Ax-wielding intruders knocked a television station off the air 30 minutes before it was to begin a series of reports on the Ku Klux Klan and neo-Nazis, a spokesman said. WOWK-TV official Bob Willis said that the Huntington, W.Va., station had no evidence about the identity of the vandals but that the FBI was investigating. “Our general manager is calling it an act of terrorism,” he said. The station had planned to begin its series--"West Virginia: A Haven For Hate?"--on its 11 p.m. newscast. Half an hour earlier, however, someone chopped cables linking WOWK with the ABC network and the station’s microwave satellite dish.